tr_model.c

quakeIII源码这个不用我多说吧

/*
===========================================================================
Copyright (C) 1999-2005 Id Software, Inc.

This file is part of Quake III Arena source code.

Quake III Arena source code is free software; you can redistribute it
and/or modify it under the terms of the GNU General Public License as
published by the Free Software Foundation; either version 2 of the License,
or (at your option) any later version.

Quake III Arena source code is distributed in the hope that it will be
useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with Foobar; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
===========================================================================
*/
// tr_models.c -- model loading and caching

#include "tr_local.h"

#define	LL(x) x=LittleLong(x)

static qboolean R_LoadMD3 (model_t *mod, int lod, void *buffer, const char *name );
static qboolean R_LoadMD4 (model_t *mod, void *buffer, const char *name );

model_t	*loadmodel;

/*
** R_GetModelByHandle
*/
model_t	*R_GetModelByHandle( qhandle_t index ) {
	model_t		*mod;

	// out of range gets the defualt model
	if ( index < 1 || index >= tr.numModels ) {
		return tr.models[0];
	}

	mod = tr.models[index];

	return mod;
}

//===============================================================================

/*
** R_AllocModel
*/
model_t *R_AllocModel( void ) {
	model_t		*mod;

	if ( tr.numModels == MAX_MOD_KNOWN ) {
		return NULL;
	}

	mod = ri.Hunk_Alloc( sizeof( *tr.models[tr.numModels] ), h_low );
	mod->index = tr.numModels;
	tr.models[tr.numModels] = mod;
	tr.numModels++;

	return mod;
}

/*
====================
RE_RegisterModel

Loads in a model for the given name

Zero will be returned if the model fails to load.
An entry will be retained for failed models as an
optimization to prevent disk rescanning if they are
asked for again.
====================
*/
qhandle_t RE_RegisterModel( const char *name ) {
	model_t		*mod;
	unsigned	*buf;
	int			lod;
	int			ident;
	qboolean	loaded;
	qhandle_t	hModel;
	int			numLoaded;

	if ( !name || !name[0] ) {
		ri.Printf( PRINT_ALL, "RE_RegisterModel: NULL name\n" );
		return 0;
	}

	if ( strlen( name ) >= MAX_QPATH ) {
		Com_Printf( "Model name exceeds MAX_QPATH\n" );
		return 0;
	}

	//
	// search the currently loaded models
	//
	for ( hModel = 1 ; hModel < tr.numModels; hModel++ ) {
		mod = tr.models[hModel];
		if ( !strcmp( mod->name, name ) ) {
			if( mod->type == MOD_BAD ) {
				return 0;
			}
			return hModel;
		}
	}

	// allocate a new model_t

	if ( ( mod = R_AllocModel() ) == NULL ) {
		ri.Printf( PRINT_WARNING, "RE_RegisterModel: R_AllocModel() failed for '%s'\n", name);
		return 0;
	}

	// only set the name after the model has been successfully loaded
	Q_strncpyz( mod->name, name, sizeof( mod->name ) );


	// make sure the render thread is stopped
	R_SyncRenderThread();

	mod->numLods = 0;

	//
	// load the files
	//
	numLoaded = 0;

	for ( lod = MD3_MAX_LODS - 1 ; lod >= 0 ; lod-- ) {
		char filename[1024];

		strcpy( filename, name );

		if ( lod != 0 ) {
			char namebuf[80];

			if ( strrchr( filename, '.' ) ) {
				*strrchr( filename, '.' ) = 0;
			}
			sprintf( namebuf, "_%d.md3", lod );
			strcat( filename, namebuf );
		}

		ri.FS_ReadFile( filename, (void **)&buf );
		if ( !buf ) {
			continue;
		}
		
		loadmodel = mod;
		
		ident = LittleLong(*(unsigned *)buf);
		if ( ident == MD4_IDENT ) {
			loaded = R_LoadMD4( mod, buf, name );
		} else {
			if ( ident != MD3_IDENT ) {
				ri.Printf (PRINT_WARNING,"RE_RegisterModel: unknown fileid for %s\n", name);
				goto fail;
			}

			loaded = R_LoadMD3( mod, lod, buf, name );
		}
		
		ri.FS_FreeFile (buf);

		if ( !loaded ) {
			if ( lod == 0 ) {
				goto fail;
			} else {
				break;
			}
		} else {
			mod->numLods++;
			numLoaded++;
			// if we have a valid model and are biased
			// so that we won't see any higher detail ones,
			// stop loading them
//			if ( lod <= r_lodbias->integer ) {
//				break;
//			}
		}
	}

	if ( numLoaded ) {
		// duplicate into higher lod spots that weren't
		// loaded, in case the user changes r_lodbias on the fly
		for ( lod-- ; lod >= 0 ; lod-- ) {
			mod->numLods++;
			mod->md3[lod] = mod->md3[lod+1];
		}

		return mod->index;
	}
#ifdef _DEBUG
	else {
		ri.Printf (PRINT_WARNING,"RE_RegisterModel: couldn't load %s\n", name);
	}
#endif

fail:
	// we still keep the model_t around, so if the model name is asked for
	// again, we won't bother scanning the filesystem
	mod->type = MOD_BAD;
	return 0;
}


/*
=================
R_LoadMD3
=================
*/
static qboolean R_LoadMD3 (model_t *mod, int lod, void *buffer, const char *mod_name ) {
	int					i, j;
	md3Header_t			*pinmodel;
    md3Frame_t			*frame;
	md3Surface_t		*surf;
	md3Shader_t			*shader;
	md3Triangle_t		*tri;
	md3St_t				*st;
	md3XyzNormal_t		*xyz;
	md3Tag_t			*tag;
	int					version;
	int					size;

	pinmodel = (md3Header_t *)buffer;

	version = LittleLong (pinmodel->version);
	if (version != MD3_VERSION) {
		ri.Printf( PRINT_WARNING, "R_LoadMD3: %s has wrong version (%i should be %i)\n",
				 mod_name, version, MD3_VERSION);
		return qfalse;
	}

	mod->type = MOD_MESH;
	size = LittleLong(pinmodel->ofsEnd);
	mod->dataSize += size;
	mod->md3[lod] = ri.Hunk_Alloc( size, h_low );

	Com_Memcpy (mod->md3[lod], buffer, LittleLong(pinmodel->ofsEnd) );

    LL(mod->md3[lod]->ident);
    LL(mod->md3[lod]->version);
    LL(mod->md3[lod]->numFrames);
    LL(mod->md3[lod]->numTags);
    LL(mod->md3[lod]->numSurfaces);
    LL(mod->md3[lod]->ofsFrames);
    LL(mod->md3[lod]->ofsTags);
    LL(mod->md3[lod]->ofsSurfaces);
    LL(mod->md3[lod]->ofsEnd);

	if ( mod->md3[lod]->numFrames < 1 ) {
		ri.Printf( PRINT_WARNING, "R_LoadMD3: %s has no frames\n", mod_name );
		return qfalse;
	}
    
	// swap all the frames
    frame = (md3Frame_t *) ( (byte *)mod->md3[lod] + mod->md3[lod]->ofsFrames );
    for ( i = 0 ; i < mod->md3[lod]->numFrames ; i++, frame++) {
    	frame->radius = LittleFloat( frame->radius );
        for ( j = 0 ; j < 3 ; j++ ) {
            frame->bounds[0][j] = LittleFloat( frame->bounds[0][j] );
            frame->bounds[1][j] = LittleFloat( frame->bounds[1][j] );
	    	frame->localOrigin[j] = LittleFloat( frame->localOrigin[j] );
        }
	}

	// swap all the tags
    tag = (md3Tag_t *) ( (byte *)mod->md3[lod] + mod->md3[lod]->ofsTags );
    for ( i = 0 ; i < mod->md3[lod]->numTags * mod->md3[lod]->numFrames ; i++, tag++) {
        for ( j = 0 ; j < 3 ; j++ ) {
			tag->origin[j] = LittleFloat( tag->origin[j] );
			tag->axis[0][j] = LittleFloat( tag->axis[0][j] );
			tag->axis[1][j] = LittleFloat( tag->axis[1][j] );
			tag->axis[2][j] = LittleFloat( tag->axis[2][j] );
        }
	}

	// swap all the surfaces
	surf = (md3Surface_t *) ( (byte *)mod->md3[lod] + mod->md3[lod]->ofsSurfaces );
	for ( i = 0 ; i < mod->md3[lod]->numSurfaces ; i++) {

        LL(surf->ident);
        LL(surf->flags);
        LL(surf->numFrames);
        LL(surf->numShaders);
        LL(surf->numTriangles);
        LL(surf->ofsTriangles);
        LL(surf->numVerts);
        LL(surf->ofsShaders);
        LL(surf->ofsSt);
        LL(surf->ofsXyzNormals);
        LL(surf->ofsEnd);
		
		if ( surf->numVerts > SHADER_MAX_VERTEXES ) {
			ri.Error (ERR_DROP, "R_LoadMD3: %s has more than %i verts on a surface (%i)",
				mod_name, SHADER_MAX_VERTEXES, surf->numVerts );
		}
		if ( surf->numTriangles*3 > SHADER_MAX_INDEXES ) {
			ri.Error (ERR_DROP, "R_LoadMD3: %s has more than %i triangles on a surface (%i)",
				mod_name, SHADER_MAX_INDEXES / 3, surf->numTriangles );
		}
	
		// change to surface identifier
		surf->ident = SF_MD3;

		// lowercase the surface name so skin compares are faster
		Q_strlwr( surf->name );

		// strip off a trailing _1 or _2
		// this is a crutch for q3data being a mess
		j = strlen( surf->name );
		if ( j > 2 && surf->name[j-2] == '_' ) {
			surf->name[j-2] = 0;
		}

        // register the shaders
        shader = (md3Shader_t *) ( (byte *)surf + surf->ofsShaders );
        for ( j = 0 ; j < surf->numShaders ; j++, shader++ ) {
            shader_t	*sh;

            sh = R_FindShader( shader->name, LIGHTMAP_NONE, qtrue );
			if ( sh->defaultShader ) {
				shader->shaderIndex = 0;
			} else {
				shader->shaderIndex = sh->index;
			}
        }

		// swap all the triangles
		tri = (md3Triangle_t *) ( (byte *)surf + surf->ofsTriangles );
		for ( j = 0 ; j < surf->numTriangles ; j++, tri++ ) {
			LL(tri->indexes[0]);
			LL(tri->indexes[1]);
			LL(tri->indexes[2]);
		}

		// swap all the ST
        st = (md3St_t *) ( (byte *)surf + surf->ofsSt );
        for ( j = 0 ; j < surf->numVerts ; j++, st++ ) {
            st->st[0] = LittleFloat( st->st[0] );
            st->st[1] = LittleFloat( st->st[1] );
        }

		// swap all the XyzNormals
        xyz = (md3XyzNormal_t *) ( (byte *)surf + surf->ofsXyzNormals );
        for ( j = 0 ; j < surf->numVerts * surf->numFrames ; j++, xyz++ )